package com.gibs.peixunapi.utils;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.ExpiredJwtException;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;

import java.util.Date;
import java.util.HashMap;

/**
 * @author liangjiawei
 * @date 2020/08/20/10:58
 * @Version 1.0
 * @Description:
 */
public class JwtTokenUtil {
        public static final String TOKEN_HEADER = "Authorization";
        public static final String TOKEN_PREFIX = "Bearer ";

        private static final String SECRET = "mysecret";
        private static final String ISS = "chen";

        // 角色的key
        private static final String ROLE_CLAIMS = "rol";

        // 过期时间是3600秒，既是1个小时
        private static final long EXPIRATION = 3600L;

        // 选择了记住我之后的过期时间为7天
        private static final long EXPIRATION_REMEMBER = 604800L;

        // 创建token
        public static String createToken(String username,String role, boolean isRememberMe) {
            long expiration = isRememberMe ? EXPIRATION_REMEMBER : EXPIRATION;
            HashMap<String, Object> map = new HashMap<>();
            map.put(ROLE_CLAIMS, role);
            return Jwts.builder()
                    .signWith(SignatureAlgorithm.HS512, SECRET)
                    .setClaims(map)
                    .setIssuer(ISS)
                    .setSubject(username)
                    .setIssuedAt(new Date())
                    .setExpiration(new Date(System.currentTimeMillis() + expiration * 1000))
                    .compact();
        }

        // 从token中获取用户名
        public static String getUsername(String token){
            return getTokenBody(token).getSubject();
        }

        // 获取用户角色
        public static String getUserRole(String token){
            return (String) getTokenBody(token).get(ROLE_CLAIMS);
        }

        // 是否已过期
        public static boolean isExpiration(String token) {
            try {
                return getTokenBody(token).getExpiration().before(new Date());
            } catch (ExpiredJwtException e) {
                return true;
            }
        }

        private static Claims getTokenBody(String token){
            return Jwts.parser()
                    .setSigningKey(SECRET)
                    .parseClaimsJws(token)
                    .getBody();
        }

}
